Crazy robot idea for this year 2

[remulasce]

I'd also note that at least one maker of the size of helium balloons that can possibly lift an FRC robot does specify that they be pressurized, and goes to great lengths to have the balloons maintain that pressure. This is partially because said balloons need to maintain a given shape, granted--but you have to wonder if it doesn't give a tad bit of extra lift.

This is still not how buoyancy works. The idea is to get the least weight to take up the most volume. The volume determines how much lift is produced. The lifting element is there to maintain volume with as little weight as possible. Because pressure of a gas is not related to the molecular weight of that gas, elements with very low molecular weights are used to match the outside atmospheric pressure, so the volume of the balloon is maintained. Your manufacturers suggest inflating beyond that pressure to give additional rigidity and in case of leaks, but once the balloon volume is full, all you're doing is putting more weight into the balloon.